桉树木材超微结构及其对干燥皱缩的影响

以多枝桉等４种桉树木材为材料，采用扫描电镜观察并分析了其导管、纤维和管胞等胞壁上的纹孔和瘤层等超微结构．结果表明，富含侵填体的桉材因其堵塞了导管间的轴向通道，并部分覆盖了管间纹孔及导管—射线间纹孔，严重影响其渗透性，是其干燥皱缩的主要原因．通过热处理后，能使多枝桉和细叶桉木材皱缩发生改善．但对赤桉和红桉无效．

Ultrastructure of Eucalyptus Wood and Its Influence on Drying Collapse

Four kinds of Eucalyptus wood have been observed with the scanning electron microscope.The ultrastructure of pits and warly layers on the cell wall of vessel, fiber and tracheid of the four kinds of wood have been analysed. The findings are as follows.The four kinds of Eucalyptus wood are rich in tylosis, which blocks the intervessel axial passway,and partly covers the intervasscular pits and vessel-ray pits, thus greatly influencing the permeability.These are the main causes leading to the drying collapse.With heat treatment,the drying collapes of E.viminalis and E.tereticornis can be relieved to a certain extent,but no improvement can be exerted on the drying collapse of E. camaldulensis and E.rubida.